A major consideration for successful maritime operations and, in particular, among the elements of an effective battle force, is the ability to communicate, most likely in the HF frequency spectrum. Present marine design and contemporary naval architecture utilize antenna designs which are, in many cases, over thirty years old. Most antenna systems on Navy surface combatant ships are not totally combat survivable.
This has proven to be especially true of the design known as the twin fan wire rope broadband HF communications antenna that is normally built for 2-6 MHz transmit/2-12 MHz receive duplex operation. The antenna consists of two sets of elements tied together and fed at one end. Each set of elements has three or more braided cables tied together at an apex end and fanned out at the other end for broadband operation. Orientation of the wires can range from horizontal to vertical. They can be positioned horizontally from the foremost to aft or at any angle with the horizontal. Although it does radiate, the twin fan antenna is primarily used to excite surrounding ship structures; at low HF frequencies, the electrical wavelength is sufficiently large that the entire ship above the water line becomes the actual radiator, or antenna. The twin fan antenna is one approach toward capacitively/inductively coupling existing tall ship structures in order to provide increased effective height and, consequently, improve radiation efficiency.
Unfortunately, many antennas, including the twin fan configuration, are "cheap kill" victims. In addition to being susceptible to damage from extreme adverse weather conditions, they are susceptible to damage from air blasts, overpressure waves, shock and vibrations and the excessively high temperatures that may result from near-miss detonations.
Thus, there is a continuing need in the state of the art for a survivable antenna design capable of broadband operation in the HF frequency spectrum that additionally presents a more compact or low profile mechanical design.